Create online ordering system for restaurant

we have a restaurant website ([login to view URL]) and we also have a very rough online ordering system where customers can add items to a shopping cart. What i would like is for the customer to be able to order by plate. ex. Plate one contains item x,y,z, etc plate two contains items a,b,c,etc We sell a mexican food item called a gordita. It is essentially a stuffed tortilla. The gordita can be stuffed with up to 3 different items. the gordita can be stuffed with only item 1, or item 1 and 2, or items 1,2, and 3. the system we have now only allows for a single gordita of a single item to be added to a single shopping cart in which the orders cannot be separated by plates. They need to be able to choose up to 3 items per gordita and up to 8 gorditas per plate. each gordita has a flat fee of $2.00 no matter how they are stuffed. it must also have a form where the customer can write special instructions if needed the customer must be able to choose the time they will pick up their order (at least 15 mins. from time of order) customer must be signed in to order or create an account with our website customer receives confirmation email with their order administrator receives an email with order and customer's contact info In the end we would like for an order to look something like this as the final product. Plate1: 1 -cheese 1- cheese, pepper strips, beans 2-steack, cheese plate 2: 2-cactus, cheese, beans 2-cheese, pepper strips